The present invention generally relates to fasteners. More particularly, this invention relates to self-countersinking fasteners configured to form a countersink hole.
Fasteners such as nails, bolts, and screws are well known in the art to hold together all types of materials including wood, metal, plastics, etc. Generally, properly installing a screw requires that one drills a pilot hole first in order to avoid cracking a receiving material due to compression. In addition, if the head of the screw is larger than the shank, and one wishes to have the top of the head flush with the receiving surface, a countersink hole must be drilled for the screw. Depending on the screw being used, this process may require multiple drills or drill-bits, and multiple steps in order to install the screw which adds to the overall construction time. To save time and reduce the steps involved in fastening materials, self-tapping screws were developed that drill their own holes, eliminating the need for a pre-drilled pilot hole. Generally, the point on a distal end of the self-tapping screw has a set of blades, which are used for drilling a pilot hole. The self-tapping screw drills the pilot hole prior to the threads of the screw entering the receiving material at a diameter that will allow for the screw to be inserted without cracking the material. However, a countersink hole must still be drilled in order for the head of the screw to be flush with the receiving surface.
In view of the above, it can be appreciated that it would be desirable if a fastener was available that was capable of forming a countersink hole without the need for a separate drilling step.